If I understand right, the goal here is to have me and the guard press 2 PP at the same turn, so vertical door at column 5 is toggle twice and don't open.
but guard will not step on a PP if there is a potion on it, unless it has the chance to push me (is it?)

A different approach could be me pressing a PP and drinking a potion, and at the same turn the guard pushing me away and step on the same PP. A setup I'm not able to do.

×The second one you mention, have the guard push you off the pressure plate the same turn you step on it. This can be tricky to set up. Some general advice:
The way to get this to work is to have the guard's pickax directly next to the pressure plate the turn right before you step on it. This means you need to be right next to the plate on the same turn that the guard is two tiles away. It takes a bit of manipulation, but it is made easier by the fact that the guard can't kill you as easily since he has a pickax.

The direction you move to step on the plate will be the direction that the decoy faces. So plan out which potions you'll need for which skipper nest ahead of time. The potion at (9,11) for instance can't be used for the bottom two nests since you'd have to be able to approach it from the north. Similarly, the potion at (7,18) can't be used for the bottom or second from the top nest.

If you need more help please feel free to post again. Alternatively you can watch a demo for this room from the title screen by clicking "Watch Demo" when you start up DROD (This will cycle through demos for all the rooms, so you may want to use it as a last resort.)

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